Brandon Rios began fight week by suggesting that, were he to lose to Mike Alvarado in the third fight of their trilogy in Broomfield, Colorado on Saturday night, he would have to seriously consider retiring. He ended it standing on the turnbuckle, pounding his chest and screaming to the ringside media “I’m back! I’m back!” Meanwhile, Alvarado sat slumped on his stool, battered and beaten after three rounds before referee Jay Nady called a halt to the contest prior to the bell sounding to mark the start of the fourth.

Boxing is the cruelest of sports at the best of times, exposing even its most successful practitioners to the kind of punishment that no other athlete would even contemplate having to endure; over the course of a career, the physical and mental beatings of multiple battles can exact a terrible toll, and the determination of all too many fighters to keep seeking that final elusive victory means that far too many careers, however successful at their peak, end in sad defeat. And the flip side to Rios’ dramatic and dominant victory is that Alvarado, a warrior who has never shirked a challenge, found himself booed by his hometown crowd for his capitulation.

Almost as sad as the brutality of his beating was the fact that, though the fight itself was mercifully brief, its denouement was foretold in predictable slow-motion during the bout’s build-up. The fact that Alvarado was arrested for firearms possession at 4:15 a.m. three weeks beforehand, the comments by some fight camp observers that he looked like the shell of a prizefighter during training, the realization that this marked his fifth successive exceptionally tough contest – after two previous bouts with Rios, and one apiece with Juan Manuel Marquez and Ruslan Provodnikov – all combined to create the impression that Alvarado was entering the ring as a dead man walking.

Still, a fighter can only fight the man in front of him, and if Alvarado was either overly-depleted or under-trained – or both – Rios was the epitome of a man who threw punches as if his future depended on them. After a brief period in the opening round when Alvarado, dry and stiff, circled and Rios, lean and hungry, sought to close him down with his jab, Rios soon found his range and raked his opponent with vicious combinations to head and body, each of them punctuated by uppercuts that sliced through Alvarado’s guard. A huge Alvarado right hand missed by a country mile, and Rios went back to bouncing punches off his foe’s head as the round ended.

Sensing that his prey was already mortally wounded, Rios flew across the ring and resumed his attack at the start of the second, unleashing a relentless barrage of punches that Alvarado, with his guard high and his legs stiff, did little to deflect or avoid. By the time six minutes had elapsed on the clock, Alvarado was giving an uncomfortably accurate impression of an unwilling bobblehead as the Rios uppercut found its mark again and again.

The assault was interrupted only by Rios being briefly felled by an Alvarado low blow in round two, and then again by the one-minute rest between the second and third frames. When the third round began, Rios resumed his brutalization. A massive uppercut snapped back Alvarado’s head with extra force, and the Colorado native dropped to his knees for an eight count. He rose to his feet and, to his immense credit, fought back as best he could for the rest of the round, but the end was clearly near and was ultimately made official by Nady after a long conversation with the boxer and his corner team.

CompuBox statistics underlined the one-sided nature of the beating. Alvarado threw just 87 punches and landed only 20, while Rios scored with 120 of 290 and outlanded his opponent in the third and final round by a staggering 52 punches to 4.

Alvarado (34-4, 24 KOs) did not exactly endear himself to the crowd by confessing that he probably had not prepared as well as he could have done. But, he defiantly asserted, “I'm not done yet. At all. I'm far from being at my best. I will be back. I guarantee to everyone in this place. I will be back.” After his performance on Saturday night, that’s far less certain than he might want to believe; but for Rios (33-2-1, 23 KOs), whose previous two outings were a lopsided loss to Manny Pacquiao and an uncomfortable disqualification win over Diego Chaves, this was a career resurgence.

“This could have been the end of my career,” the victor said afterward. “I have a lot of gas left in the tank. This was my best fight ever.” And then he repeated the cry he had let loose at the end of the fight.